hiddev: Add support for opening hid devices by vendor and product IDs.

Signed-off-by: Timo Kokkonen <kaapeli@itanic.dy.fi>

diff --git a/hiddev.c b/hiddev.c
index b4420197269c6155523016ecbbb54c62eb65daad..7cf7239e3b5bc57b2961be6344ff6889cafc55e4 100644 (file)
--- a/hiddev.c
+++ b/hiddev.c
@@ -2,16 +2,20 @@
 #include <stdlib.h>
 #include <unistd.h>
 #include <sys/ioctl.h>
+#include <sys/types.h>
 #include <linux/hiddev.h>
 #include <errno.h>
 #include <string.h>
 #include <fcntl.h>
+#include <dirent.h>
 
 #include "hiddev.h"
 #include "utils.h"
 
 #define PRINT_FIELD(level, field) trace(level, #field ": %04x\n", field)
 
+#define HIDDEV_PATH "/dev/usb/"
+
 int hiddev_read(unsigned char *data, int bufsize, int fd)
 {
        struct hiddev_event readBuffer[READ_BUFFER_LENGTH];
@@ -87,23 +91,25 @@ static int get_usagecode(int fd)
        return uref.usage_code;
 }
 
-int hiddev_open(const char *device_path, int *usage_code)
+static int _hiddev_open(const char *device_path, int *usage_code,
+                       int vendor_id, int product_id)
 {
        struct hiddev_devinfo device_info;
        struct hiddev_report_info rinfo;
        int ret, error;
        int fd;
+
+       trace(3, "Opening device %s\n", device_path);
        fd = ret = open(device_path, O_RDWR);
 
        if (fd < 0)
                goto err;
 
-
        rinfo.report_type = HID_REPORT_TYPE_OUTPUT;
        rinfo.report_id = HID_REPORT_ID_FIRST;
        ret = ioctl(fd, HIDIOCGREPORTINFO, &rinfo);
        if (ret < 0)
-               goto err;
+               goto err_close;
 
        PRINT_FIELD(3, rinfo.report_type);
        PRINT_FIELD(3, rinfo.report_id);
@@ -112,12 +118,12 @@ int hiddev_open(const char *device_path, int *usage_code)
        *usage_code = get_usagecode(fd);
 
        if (*usage_code < 0)
-               return -8;
+               goto err_close;
 
        ret = ioctl(fd, HIDIOCGDEVINFO, &device_info);
 
        if (ret < 0)
-               goto err;
+               goto err_close;
 
        PRINT_FIELD(3, device_info.bustype);
        PRINT_FIELD(3, device_info.busnum);
@@ -128,11 +134,65 @@ int hiddev_open(const char *device_path, int *usage_code)
        PRINT_FIELD(3, device_info.version);
        PRINT_FIELD(3, device_info.num_applications);
 
+       if (product_id && vendor_id) {
+               if (product_id == device_info.product &&
+                       vendor_id == device_info.vendor)
+                       return fd;
+               trace(3, "Vendor and product IDs don't match\n");
+               goto err_close;
+       }
+
        return fd;
 
+err_close:
+       close(fd);
 err:
        error = errno;
        printf("Error opening device %s: %s\n", device_path, strerror(error));
        return ret;
 }
 
+int hiddev_open(const char *device_path, int *usage_code)
+{
+       return _hiddev_open(device_path, usage_code, 0, 0);
+}
+
+int hiddev_open_by_id(int vendor_id, int product_id, int *usage_code)
+{
+       struct dirent *dirent;
+       DIR *dir;
+       int error, fd;
+       char path[256];
+
+       dir = opendir(HIDDEV_PATH);
+       if (dir == NULL) {
+               error = errno;
+               printf("Failed to open directory %s: %s\n", HIDDEV_PATH,
+                       strerror(error));
+               return -error;
+       }
+
+       while ((dirent = readdir(dir))) {
+               if (strncmp(dirent->d_name, "hiddev", sizeof("hiddev") - 1))
+                       continue;
+
+               path[0] = 0;
+               strncat(path, HIDDEV_PATH, sizeof(path) - 1);
+               strncat(path, dirent->d_name, sizeof(path) - 1);
+
+               fd = _hiddev_open(path, usage_code, product_id, vendor_id);
+               if (fd < 0)
+                       continue;
+               return fd;
+       }
+
+       if (errno) {
+               error = errno;
+               trace(0, "Error reading directory %s: %s\n", HIDDEV_PATH,
+                       strerror(error));
+               return -error;
+       }
+
+       trace(0, "Canno't find any mathing hiddev devices\n");
+       return -1;
+}

diff --git a/hiddev.h b/hiddev.h
index a37c60f005a929bc589d7c650604e7b16b8d6e27..2d5f948a2bfc77aa155bec31a289f3bac0914136 100644 (file)
--- a/hiddev.h
+++ b/hiddev.h
@@ -6,5 +6,6 @@
 int hiddev_read(unsigned char *data, int bufsize, int fd);
 int hiddev_write(const unsigned char data[64], int fd , int usage_code);
 int hiddev_open(const char *device_path, int *usage_code);
+int hiddev_open_by_id(int vendor_id, int product_id, int *usage_code);
 
 #endif